Cutting tools are generally used for removing material from a workpiece, using a cutting edge of the tool. There is a great plurality of cutting tools, each configured for performing a different cutting operation, i.e. Removing material from the workpiece in a specific manner. Examples of such operations are milling, turning, wedging, drilling etc., and each cutting tool and it corresponding cutting edge designed so as to perform their respective operation.
Cutting tools can generally divided into two types: integral cutting tools and combined cutting tools, where the former has an integral cutting edge formed in the tool itself, while the latter comprises a cutting tool holder and a cutting insert formed with a cutting edge, the insert being configured for mounting onto the cutting tool holder.
There are various mechanisms and manners in which a cutting insert can be mounted onto the cutting tool holder, including fastening screws, securing pins, snap fittings and bayonets.
With particular reference to drilling tools, the bayonet arrangement is widely used for mounting a drilling head onto the cutting tool holder. Specifically, the drill head (formed with a cutting edge/s) is formed with a latch portion and the cutting tool holder is formed with a corresponding recess, configured for receiving the latch portion. The arrangement is such that during operation of the drilling tools, revolution of the drilling tool operates against the bayonet, tightening the secure engagement between the cutting tool holder and the drill head.